The by now famous exclusion problem for mental causation admits only one possible solution, as far as I can see, namely: that mental and physical properties are linked by a vertical relation. In this paper, starting from what I take to be sensible premises about properties, I will be visiting some general relations between them, in order to see whether, first, it is true that some vertical relationship, other than identity, makes different sorts of causation compatible and second, whether physical and mental properties can be pairs of such relationship